My primary work desktop machine blew up recently so I’m slowly but surely installing software on a new machine. I use several different programming languages on a regular basis, including Python along with its NumPy and SciPy libraries.

Even though I’ve installed the SciPy stack several times, I ran into a couple of glitches this time around. There are 6 steps to install the SciPy stack:

1. Determine which versions of NumPy and SciPy have
binary installers.
2. Determine which version of Python will work with
the NumPy and SciPy libraries you'll be installing.
3. Install the correct version of Python.
4. Install the correct version of NumPy.
5. Install the correct version of SciPy.
6. Test.

The first step is to find (but NOT install) a binary installer for NumPy. I went to sourceforge.net/projects/files/NumPy and clicked on different versions until I found version 1.10.2 that had a binary installer named blah blah win32 blah python3.4 blah.

Next I went to sourceforge.net/projects/files/SciPy and clicked on different versions until I found a binary installer for version 0.16.1 named blah blah win32 blah python3.4 blah.

At this point I know I need a Win32 version of 3.4 Python. I went to python.org/downloads and found a link to Python 3.4.4 (i.e., 3.4) and after clicking on its Download link I found a Windows x86 MSI installer link.

I accepted all the install defaults which placed Python at C:\Python34. The install does not add the path to the System PATH environment variable so I had to do that manually.

With Python installed I went back to the NumPy install page and used the binary installer. The installer correctly found my existing Python at C:\Python34 — if you don’t see that, you’re hosed. Uninstall Python and start over.

After NumPy installed I went back to SciPy and used the binary installer. No problems installing SciPy.

Finally to test everything, I launched a cmd shell and entered the commands:

C:\> python
>>> import numpy as np
>>> import scipy as sp
>>>

Because I got no errors, I was pretty sure the SciPy stack was installed correctly.